City car charging networks are nothing new — not even in Houston, which has some plans to install chargers from Coulomb Technologies in central parking garages. Still, NRG calls eVgo the first network to be completely funded by private sources — and it’s also taking a page from the cellphone industry in charging flat monthly rates for a variety of different uses of charging.

Charging plans for eVgo will range from $50 to $90 a month on fixed three-year contracts, with the cheaper rates for people who only want “Level 2” chargers, capable of adding about 25 miles of range per hour of charging, installed at their homes. The more expensive plans give access to the publicly located chargers, which will be fast chargers capable of adding some 30 miles of range in as few as 10 minutes. Walgreens will host Aerovironment chargers at 10 Houston stores, and the Best Buy, H-E-B and Spec’s chains have also agreed to participate.

These flat, fixed monthly charges — a common attribute to electricity plans in Texas’ deregulated market — are expected to earn NRG a profit over the lifetime of the contracts, NRG CEO David Crane said in a Thursday morning teleconference. NRG is hoping to have about 1,000 customer signed up in about a year, he said.

Nissan North America has agreed to make eVgo charging services the exclusive charging option for Houston-area buyers of the Nissan LEAF electric sedan, said Arun Banskota, the NRG senior vice president heading up the eVgo project. Other automotive partners, including Smart USA, U.S. dealer of Daimler AG’s Smart ForTwo mini vehicle, and major Houston area dealers Gulf States Toyota, haven’t yet revealed the terms of their arrangements with NRG, he said.

As for who will sell the electricity to charge the cars of eVgo customers, two of the companies belong to NRG — Houston-area power retailer Reliant Energy and recently acquired renewable power seller Green Mountain Energy. Other retail power participants will be Direct Energy and TXU Energy — an unusual arrangement in a market where retail electricity providers are in hot competition with one another.

How the eVgo model might work in more regulated power markets remains to be seen. For example, car rental company Hertz was reported to be planning to supply vehicles for testing of charging stations in other Texas cities including Dallas, Austin and San Antonio. But the last two cities are provided power by municipal utilities that don’t participate in Texas’ deregulated market. Crane told reporters that NRG was exploring different arrangements to provide eVgo services to customers in those cities.

What about people who haven’t signed up for eVgo, but still want to plug in for emergency charging at one of the public stations? They will have access, Banskota said — but NRG hasn’t yet determined how they’ll be charged for the power they use, and it won’t be part of the rollout right away.

NRG also said it was a bit early to answer some other questions about how customers of other utilities or car charging services might interact with eVgo in the future. With the world of plug-in vehicles and charging stations still in its infancy, there are plenty of kinks to be worked out, after all.

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